Puppet-valve for internal-combustion engines.



F. D. SHEPHERD.

PUPPET VALVE FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED FEB a, 1511.

1,258,480. I Patented Mar. 5, 1918.

2 SHEETS-SHEET l.

ifo al. 15

F. 0. SHEPHERD. I I vPUIIET VALVE FOR INTERNAL COMBUSTION ENGINES.

v v 1 APPLICATION FILED FEB. HV 1917. 1,258,480.

I Patented Mar. 5, 1918.

FLRAN K D. SHEPHERD, F SALT LAKE CITY, UTAH.

PUPIET-VALVE FOR INTERNAL-COMBUSTION ENGINES.

Specification of Letters Patent.

Patented Mar. 5, 1918.

Application filed February 8, 1917. Serial No. 147,396. 7

To all whom it may concern:

Be it known that I, FRANK D. SHEPHERD, a citizen of the United States, and resident of Salt Lake City, in the county of Salt Lake and in the State of Utah, have in vented a certain'new and useful Improvement in Puppet-Valves for Internal-Combustion Engines, and do hereby declare that the following is a full, clear, and exact description thereof.

My invention relates to puppet valves and especially those adapted for usc'with inbi rims, and my object,

provide a valve congcnera I A I struction which will increase the power oil:

the engine, to put it differently, will secure economy of use of fuel; which will elliciently and certainly perform its functions of closing and opening, so that when closed. 0 upon. its seat it can be depended upon to cut oil completely the flow of gas, and when open will allow free and ample passage; will be simple of construction, hence contributing to economy of manufacture as. well as eliminating danger of becoming disordered; and will be readily and easily accessible for removal and replacement of the parts, whose removal and replacement may be desirable, and for the attainment. of

;this object and others which will be understood by those skilled in the art when the characteristics of the valve embodying my invention are understood from the accompanying drawings and description. my in vention consists in the valve mechanism constructed su stantially as hereinafter specificd and claimed.

In the accompanying drawings which illustrate several forms, or embodiments of my invention Figure 1 is a vertical section through an internal combustion engine having a valve embodying my invention;

Fig. 2 is a similar view. but showing only the valve'mechanism and immediately adjacent parts of another embodiment of my invention Fig. 3 is a view similar to Fig. 2, but showing still. another form of valve embodving my invention;

gasket 19 clamped between the plug tainer cap and hollow filling piecediiferent from that shown in Fig. 1.;

Fig. 6 is a vertical section showing a type of engine having a detachable head with which the spring housing is integrally formed;

Fig. 7 is a top plan view with a portion 'broken away showing said detachable head provided with a series of valves.

Giv ng a detail description of the construction shown in Fig. 1 of the drawing, the engine cylinder 10 shown is of the type having the head 11 cast integral therewith and conncwd with said head there are as many 'pu'pi'ici v as, in the judgment of the designer it proper, or desirable to employ, but for the purpose of disclosing my invention to those skilled in the art it is not necessary to show and describe more than one valve mechanism, which thus is to be taken as rv-qnescntative, or typical for both the intake and the exhaust, and for as many as it may be desirable, or expedient to cn'iploy. My invention, as will be evident, has to do with the valve construction and not with [the number employed (although itsv qnrsiruct-ion is such as to render unnecessary nniltiplication of the number) nor is my invention concerned with the par ticular typc, or construction of the engine, or the nu-clianizmi for lifting the valve from its scat. in the engine head eccentric to the cylinder, I provide an internally threaded opening 12 which extends from the outer end of the head into the port 13, which is controlled by the valve mechanism. for which purpose, directly in line with said opening 12 and on the opposite side of the port it has a beveled seat 14: for the puppet valve 15 whose face. or rim is correspondii'igly beveled so that it, closely, and in a gas tight manner, its its seat. Screwed in said hole 12 is one cud cl a. cylindrical shell 16, a gas tight joins is formed between a shoulder on said slaw. andthc outer side of the piston head by an interposed washer, or gasket 17. The outer end of said shell is closed in a gas tight manner by a plug 18 which is screwed into said outer end and a gas tight joint formed by a washer, or and a shoulder, or hearing on the shell. At the opposite inner end of the shell it is closed save for a central hole 20 through which passage, with a sliding fit, a stem 21 on the has valve, said stem reaching into the chamber in said shell and having mounted upon it a disk, 'or head 22 of substantially the diameter of the chamber in the shell and between which head and the inner side ofthe filling plug 18 is interposed an expansible coil spring 23, which by pressure on the valve transmitted through said head and stem yieldingly holds the valve to its seat from which 1t is lifted by the usual lifter cam 24 acting through a stem 25 on the opposite side of the valve from the stem 21. It will be observed that the spring 23 is concentric with the valve axis, and hence,

exerts a pressure on the valve which is balanced, that is to say, it is accompanied by no sidewise, or tilting action, and hence, tendency to wear of the stem and guide on one side with a consequent tilting, or cooking of the valve on its seat'enough to cause leakage. Another evil resulting from such unequal wear, isthe sucking in of air which. spoils the mixture of gas from the carbureter and thus the power of the engine is impaired. "A serious objection to leakage of gas past the valve is erosion, or cutting by the as that takes place. The spring bearing ead 22 is applied to the valve stem 21 bymeans of a central hole which fits the reduced endof the valve stem 21 and is seated upon a shoulder 26 formed by the reduction of the end of the valve stem and the latter projects slightly beyond the head 22 to give access to a suitable tool for grinding the valve on its seat, the valve stem having a proper formation for en-' gagement by said tool. Said head has a spring-engagin surface that is preferably concave, or dis ed so as to afford a good bearing for the spring and within the spring it has a short extension over which the spring looselv fits, and from end to end it is perforated as bymeans of several holes 27 whose pur ose is to prevent such suction between t e inner sides of the head and the adjacent stationary surface as would hinder, or obstruct erfectly free movement of the head and of t e valve when the latter is lifted from its seat and to prevent the existence of an air cushion that would ob struct, or hinder the seating movement of the valve." Between the head 22 and the innor end of the shell 16 isa ring 28 of absorbent fire-proof, or non-heat conducting material which snugly fits the annular space around the valve stem 21, and said ring being saturated with some lasting lubricant, it supplies such lubricant to the valve stem and thus eases its movements in'the hole in the inner end of the shell 16. Moreover said ring 28 also performs the function of ack ing the joints so as to prevent the lea age, or escape of gas into the shell 16, and when made .of' non-heat conducting material it protects the spring within the shell 16 from the high temperatures of the gas passing through the port 13. There is no commune cation between the interior of the shell. and the outside air.

To reduce the unoccupied space, or vol ume in the shell. 16 ton minimum and thus preclude the presence in said shell of any more than a negligible quantity of gas, should leakage into the shell 16 occur, the plug 18 has an inward cylindrical extension 29 that constitutes a filhng piece within the spring coils made as large in diameter and. of as great length is possible withoutinterioring with the play of the spring and the movements of the valve. llreferably, as shown in Fig. 1, the plug and its lillii'zg piece extension are made hollow so as to achieve the'important advantages of making the heat radiating surface of as great an area as possible and thereby safeguard the spring from injury by high temperatures and also to economize in material and in cost of manufacture by the reduction ofweight of metal required. The portion of the hollow chamber in the plug may he flat sided for the application oi a turning wrench, or device for the unscrewing of the plug from the shell 16 or its screwing thereinto. At its inner end the filling piece has a cavity 30 of the size to receive the extremityof the valve stem 21 when the latter is lifted to its highest position and thus avoid contact of the filling pieces and of the valve stemwhile making the length of the filling pieces as great as possible. As a further precaution against undue heating, the radiatin surface of the shell 16 may be increased. y the familiar expedient of fins, or ribs on its exterior.

In order to give ample body to the valve 15 so that it may resist warping or bending out of shape, it is given a substantially (3011b cal form on its side toward the stem 21 so that it gradually thickens in diameter from the stem 21 to the seat-engaging face and 1m to accommodate this thickened portion when the valve lifts from its seat the end of the shell 16 toward the valve is provided with a correspondin ly shaped cavity 31 which extends inward from the plane of the outer wall of the port 13. Thus ample space for the movement of the valve is provided without unduly increasing the depth of the port 13. The valve stem 25, which in Fig. 1 is shown integral with the valve pames through a guide 32 and beyond the latter its end is engaged by a lifter 33 which in turn. is acted upon by the lifting cam 24 but as these parts which are concerned in lifting the valve do not concern my invention it is 126 unnecessary to describe the same in any more detail and in respect of such matters it is to be understood that I in nowise limit my invention thereto.

Referring to the construction illustrated in Figs. 2 and 4, it will be found to be in all respects similar to that shown in Fig. 1, excepting that the shell-closing plug 180 and the extension 290 thereof forming the filling pieces are solid and for the application of a wrench, or turning tool a solid projecting hexagonal head 18.1 is provided and the gas tight joint is produced by a flange 182 and a gasket 183 lying between said flange and the adjacent end of the shell 16.

Tn Fig. 5 the shell closing plug 280 and its extension 28]. forming the filling piece combine the ClltLIEIClZCl'lSlLlCS of the corresponding elements shown in Figs. 1 and 2, in that the plug and filling piece are hollow and there is an external head 282 for the application of the wrench, or turning tool.

In Figs. 6 and 7, I illustrate a construction suitable for engines with a detachable head 34 which permits the cylindrical shell, or container 160 to be made integral with the head and instead of making the shell itself removable its outer end is closed by a cap plate 35 secured by screws, or bolts 36. The closing plate 35 may be a continuous one, as shown in Fig. 7, to serve for the plurality, or series of shells, or containers, but, of course, instead of using a single closing plate each shell, or container, as shown in theother figures of the drawing may have its own individual closing plug, or cap. Referring to the construction shown in Fig. 3, it will be found to differ from that shown in Fig. 2, in the respect that the valve stem 250 isscparate from the valve, and in making the filling piece 291 separate from the shell closing plug 184, and in utilizing such separate construction to provide for adjusting the tension of the valve seating spring 23. This is accomplished by pro viding a head, or flange 292 on the filling piece 291, which affords a bearing for the outer end of the spring 23 and by passing an adjusting screw 185 through a central tapped hole in-the plug 184. A look nut 186 is provided to hold the screw 185 to the desired adjustment. In Fig.3 the toolengaging portion of the valve stem 21 is an angular head instead of a slot, as is shown in Fig. 1.

I have shown various forms, or embodiments of my invention. in order that it may be. understood that I realize that such inventionmay exist in different forms, It, of course, can have embodiments other than those selected by way of example and, hence, it is to he understood that I regard myself as entitled to its embodiments in still other terms than those shown in the drawings.

Having thus described my invention what claim is- 1. The combination of an engine cylinder having a valve controlled passage with a valve seat, a puppet valve, a shell or conried by said tainer, a 5 ring in said shell, a stem reaching from t e valve into said shell, a springengaging head on said stem, and an opening or passage in said head establishing cornmunication between spaces in the shell on opposite sides of said head.

2. The combination of an engine cylinder having a valve controlled passage with a valve seat, a puppet valve, a shell or container in alinement with the valve and closed at its end toward the valve excepting for a stem guiding hole, a springin said shell, a stem reaching from the valve .into said shell through said hole and slidably fitting the same. a wring-engaging head on said stem, and a ring of heat resisting material surrounding and fitting the stern in said shell at the side of the head toward said valve controlled passage.

3. The combination of an engine cylinder having a. valve controlled passage with a valve seat, a puppet valve, a shell or container, a spring in said shell, a stem reaching from the valve into said shell, a springengaging head on said stem, and a ring surrounding the stcm in said shell at the side of the head toward said valve controlled passage, said ring carryii'ig a lubricant for the stem.

4. The combination of an engine cylinder having a valve controlled passage With a valve seat, a puppet valve, a shell or container, a spring in said shell acting to hold the valve yieldingly to its seat, a stem extending from the valve into said shell, the valve having a tapering thickened portion reaching to the stem, and a surface opposite the valve seat that has a cavity to receive said thickened portion of the valve.

5. The combination of an engine cylinder having a valve-controlled passage with a valve seat, a puppet valve, a shell or container closed to the external air, a coil spring in said shell, said spring acting on the valve to hold it yieldingly to its seat, a removable cap for the outer end of said shell, and a filling piece projecting inward from and carcap and extending partially through the coils of the spring.

6. The combination of an engine cylinder having a valve-controlled passage with a valve seat, a puppet valve, a shell or container, a coil spring in said shell, said spring acting on the valve to hold it its seat and a filling piece extending partially through the coils of the spring, said filling piece being hollow and its interior being in communication with air.

7. The combination of an engine cylinder having a valve-controlled valve seat, a puppet valve, a shell or con tainer, a coil spring in said shell, said spring acting on the valve to hold it yieldingly to its seat, and a plug closing an opening in yieldingly to the external passage with a the outer end or said shelland having an inward extension within the coils of the spring, said plug and said extension. being hollow and opening to the external air.

8. A puppet valve for gas engines com vprising; a head having a seating face on one .said reduced portion of the stem having a form to receive a grinding tool. 7

9. A puppet valve for gas en ines comprising a head having a seating ace on one side, a "guiding stem on its opposite side, said stem havin a reduced shoulder-forming portion, a s e11 in which said portion extends, a head on said reduced portion and bearing against said shoulder, a coil spring in said shell bearing against said head, and a removable cap against which the spring bears having a projection forming a filling piece that reaches into the spring.

In testimony that I claim the foregoing I have hereunto set my hand.

FRANK D. SHEPHERD. 

